Method and apparatus for use in processing radiation sensitive elements

ABSTRACT

An apparatus and method for use in in-packet processing of photographic film. A liquid impermeable packet containing an exposed film has processing fluid injected into the packet about the film and the film is processed by placing the packet on a moveable support and subjecting the fluid to random agitation as the packet is moved along a predetermined path by asynchronously reciprocating a plurality of beams to squeeze different portions of the packet.

United States Patent Inventor Andrew Green Harrow, England Appl. No. 40,065 Filed May 25, 1970 Patented Oct. 12, 1971 Assignee Eastman Kodak Company Rochester, N.Y. Priority June 24, 1969 Great Britain 31875/69 METHOD AND APPARATUS FOR USE IN PROCESSING RADIATION SENSITIVE ELEMENTS 6 Claims, 3 Drawing Figs.

US. Cl 95/89 R, 95/13, 250/69 Int. Cl G03d 5/02 Field of Search 95/13, 89 R, 99; 29/121 R, 125; 107/12, 34, 36, 38,10;

References Cited UNITED STATES PATENTS 2,797,625 7/1957 Fairbank 95/13 3,008,220 11/1961 Sammarco 29/125 Primary Examiner-John M. Horan Assistant Examiner-Alan Mathews Attorneys-Walter O. Hodsdon and Robert F. Crocker ABSTRACT: An apparatus and method for use in in-packet processing of photographic film. A liquid impermeable packet containing an exposed film has processing fluid injected into the packet about the film and the film is processed by placing the packet on a moveable support and subjecting the fluid to random agitation as the packet is moved along a predetermined path by asynchronously reciprocating a plurality of beams to squeeze different portions of the packet.

PATENTED um 1 219m SHEET 1 [1F 2 PATENTED nun 219m SHEET 2 [IF 2 ANDREW GREEN 65% vanzf A TTORNEYS METHOD AND APPARATUS FOR USE IN PROCESSING RADIATION SENSITIVE ELEMENTS BACKGROUND OF THE INVENTION The present invention relates to the processing of radiation sensitive elements. More particularly, the invention relates to the processing of photographic elements such as dental radiographs.

Processing of dental radiographs and an apparatus for use in such processing has been described in copending US. application Ser. No.705,329 filed Feb. 14, 1968 in the names of Gerald I. P. Levenson and myself, now US. Pat. No. 3,575,099, and assigned to the same assignee as this application. Briefly, this process comprises injecting a quantity of processing fluid into a previously exposed film pack such as a liquid impermeable envelope containing X-ray film and then agitating the fluid about the film, the period of agitation usually being made to correspond to the required processing time.

As described in that application, an agitator for this purpose has a fixed wall against whicha fluid-containing film pack is placed to be acted upon by a seesaw arrangement which, in operation, squeezes the film pack against the fixed wall to cause the processing fluid inside the pack to flow alternately from side to side within the envelope. While such an apparatus does produce satisfactory results, it is necessary either to terminate the period of agitation manually, or to incorporate in the apparatus a timer mechanism which may be preset so as to terminate such periodautomatically.

Another disadvantage with this apparatus is that ideally the flow of the fluid in the packet should be random so as to give even processing in the minimum time. The apparatus described in the above-mentioned application did not give even agitation because its see-saw squeezing action did not produce a random flow of processing solution. In addition, because the pack was held vertically the heavy waste products of fixation were allowed to sink to the bottom with the result that in this area fixation took longer and development was relatively more active.

Although agitation by hand gives optimum performance because it sets up a random flow of solution, it is inconvenient and a need has developed for a procedure or apparatus which can achieve the results of manual processing but which can free one from this tiresome task.

Therefore, it is an object of this invention to provide an improved method and apparatus for use in in-packet processing of a radiation sensitive element which provides even processing by mechanical means.

It is a further object of this invention to provide an improved method and apparatus for use in in-packet processing of a radiation sensitive element which eliminates the need for a separate process time.

SUMMARY OF THE INVENTION The apparatus forming applicant :2 invention includes means for supporting and for moving along a predetermined path a packet having both an exposed radiation sensitive element and processing fluid contained within the packet and a plurality of reciprocable packet squeezers which cooperate with the support means for squeezing different portions of the packet to agitate the fluid as the packet is being moved along the path.

The method forming applicants invention includes the steps of positioning the fluid-containing packet on a support, moving the packet along a predetermined path and while the packet is being moved, asynchronously reciprocating packet squeezers against different portions of the packet to agitate the fluid so as to process an image on the element. By the use of the term asynchronously reciprocating to define the relationship of the packet squeezers, it is meant that reciprocation of the squeezers is such that not all of the squeezers are squeezing the packet at the same time.

BRIEF DESCRIPTION OF THE DRAWING The invention and its objects may be more fully understood from the following description, when it is read with reference to the accompanying drawing in which:

FIG. 1 is a schematic perspective view of the apparatus;

FIG. 2 is a plan view of the apparatus; and

FIG. 3 is an end view of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, the apparatus comprises an endless belt ll having a thin layer of rubber 23 on its outer surface. A pair of rollers 12 and 13, one of which is driven by means of an electric motor through a suitable reduction gear arrangement 15, support the belt 11. for travel through an endless path. Both of the rollers 12 and I3 are rotatably supported by a pair of sidewalls l6 and I7 which form the main chassis members of the apparatus. A flat path along which a film pack containing processing fluid may be carried is pro vided by backing up the belt ll on its upper track by a flat sold member (not shown) which is also supported rigidly by the sidewalls 16 and 17.

Disposed above the belt 11 and in superposed relationship to the packet path is an array of eight rigid beans 18 which extend the length of the flat portion of the belt 11 and which are mounted transverse the packet path in side-by-side relationship on a pair of matched Camshafts l9 and 20, each having a plurality of randomly oriented eccentric portions, one. for each beam. Camshafts 19, 20 extend through transverse openings in the beams l8 and are rotatably supported the sidewalls H6 and 17. By means of a chain and sprocket arrangement 21, the two carnshafts are coupled for synchronous rotation, the driving force being supplied by an electric motor 22 which is coupled to one of the camshafis.

Advantageously, the flat path defined by the upper track of the belt 11 is in a horizontal plane so that the film inside a film pack will likewise be flat and horizontal during agitation. This arrangement is preferable because as has been mentioned above, it has been found that if a film pack containing processing fluid is held in an upright position during agitation, i.e. with the film inside the pack vertically disposed, the heavy waste products of fixation sink to the bottom edge of the pack with the result that in this area fixation takes longer and development is relatively more active.

It will be appreciated that the disposition of the beams 18 and the degree of asynchronous reciprocation of adjacent beams, as determined by the relationship of the respective eccentrics of the camshafts l9 and 20, is such as to allow the passing through the apparatus of a fluidwontaining film pack carried on the endless belt 11, with the beams I8 each bearing down intermittently on a portion of the film pack to squeeze the pack and displace processing fluid therein from the squeezed portion. The beams 18 are reciprocated so that at all times they will be parallel to the upper track of belt 11. The degree of agitation of the processing fluid inside the pack de pends, of course, on the speed of the belt 11 and the rate of reciprocation of the beams 18, either of which may be varied independently of the other.

In the embodiment described, the endless belt 11 is made up of perforated 70 mm. film base having a thin layer of rubber 23 on its outer surface, and the lengths of the flat portion of the belt 11 and of the beams 18 are 15 inches, each'beam being about A inch wide and being made of a material which slips quite readily across the surface of the. film pack during squeezing.

In operation, a plastic dental packet containing the exposed film is filled with processing solution in themanner described in the above-mentioned application Ser. No. 705,329. Excess air is squeezed out and the solution spread over the emulsion with a few seconds manual manipulation of the packet. The packet is then pushed into the entrance of the agitator.

It is preferred to have the camshafts l9 and 20 rotating at between 50 and 200 r.p.m. and to run the belt at a speed such that the film pack will travel through the apparatus in the exact time required for processing the film inside the packet, e.g. 4% minutes in the case of dental radiographs. Processing of the packet will be complete when the package reaches the end of the belt, and the need for a separate timer is eliminated.

it will be appreciated, however, that tracks other than a flat horizontal track may be used, for example, the curved surface of a drum may be used in place of the belt. A plurality of parallel camshafts may be employed so that the eccentrics thereof directly agitate the pack without using beams. Alternatively, the camshafts may operate cam followers to effect the agitation. A single motor may be used to drive both the belt and the camshafts.

Photographic elements other than dental radiographs may be processed in liquid-impermeable envelopes in accordance with the method of the invention and the dimensions of the apparatus may be chosen to accommodate packs of various sizes.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

I claim:

I. An apparatus for use in processing an image on an exposed radiation sensitive element, said element being positioned in a packet which also includes processing fluid, said apparatus comprising:

means for supporting said packet and for moving said packet along a predetermined path;

a plurality of reciprocable packet squeezers, said squeezers being cooperable with said support means to squeeze different portions of said packet as said packet traverses said path; and

means coupled to said squeezers for asynchronously reciprocating said squeezers against different portions of said packet as said packet traverses said path to agitate said fluid contained therein so as to process said image on said element.

2. The invention according to claim 1 wherein said squeezers are positioned in superposed relationship to said path and arranged transversely of said path.

3. The invention according to claim 2 wherein said reciprocating means includes a camshaft.

4. The invention according to claim 2 wherein said squeezers are comprised of beams arranged in side-by-side relationship and which extend longitudinally with said path.

5. The invention according to claim 1 wherein said support means comprises a horizontal endless belt;

said squeezers comprise beams arranged in side-by-side relationship transversely of said path and which extend longitudinally with said path; and

said reciprocating means includes a camshaft on which said beams are mounted.

6. A method for processing an image on an exposed radiation sensitive element, said element being positioned in a packet which also includes processing fluid, said method comprising the steps of:

positioning said packet on a support;

moving said packet along a predetermined path; and

while said packet is being moved, asynchronously reciprocating packet squeezers against different portions of said packet to agitate said fluid contained therein so as to process said image on said element. 

1. An apparatus for use in processing an image on an exposed radiation sensitive element, said element being positioned in a packet which also includes processing fluid, said apparatus comprising: means for supporting said packet and for moving said packet along a predetermined path; a plurality of reciprocable packet squeezers, said squeezers being cooperable with said support means to squeeze different portions of said packet as said packet traverses said path; and means coupled to said squeezers for asynchronously reciprocating said squeezers against different portions of said packet as said packet traverses said path to agitate said fluid contained therein so as to process said image on said element.
 2. The invention according to claim 1 wherein said squeezers are positioned in superposed relationship to said path and arranged transversely of said path.
 3. The invention according to claim 2 wherein said reciprocating means includes a camshaft.
 4. The invention according to claim 2 wherein said squeezers are comprised of beams arranged in side-by-side relationship and which extend longitudinally with said path.
 5. The invention according to claim 1 wherein said support means comprises a horizontal endless belt; said squeezers comprise beams arranged in side-by-side relationship transversely of said path and which extend longitudinally with said path; and said reciprocating means includes a camshaft on which said beams are mounted.
 6. A method for processing an image on an exposed radiation sensitive element, said element being positioned in a packet which also includes processing fluid, said method comprising the steps of: positioning said packet on a support; moving said packet along a predetermined path; and while said packet is being moved, asynchronously reciprocating packet squeezers against different portions of said packet to agitate said fluid contained therein so as to process said image on said element. 